/**
  * {@inheritDoc}
  */
 protected function getSystemIdForNodeUuid($uuid, $workspaceName = null)
 {
     if (empty($this->caches['nodes'])) {
         return parent::getSystemIdForNodeUuid($uuid, $workspaceName);
     }
     if (null === $workspaceName) {
         $workspaceName = $this->workspaceName;
     }
     $cacheKey = "id: {$uuid}, " . $workspaceName;
     $cacheKey = $this->sanitizeKey($cacheKey);
     if (false !== ($result = $this->caches['nodes']->fetch($cacheKey))) {
         if ('false' === $result) {
             return false;
         }
         return $result;
     }
     $nodeId = parent::getSystemIdForNodeUuid($uuid, $workspaceName);
     $this->caches['nodes']->save($cacheKey, $nodeId ? $nodeId : 'false');
     return $nodeId;
 }